[0001] The present invention relates to a method and an apparatus for removal of contaminants
from human and animal, tissues. The method and apparatus are particularly useful for
treatment of tumors.
[0002] In medical circles, it is well known the widely proven regression effect produced
on primary and secondary tumors by hyperthermia.
[0003] Many studies, both biological and clinical, have been successfully completed, relying
on localized or total-body hyperthermia.
[0004] However the success rate, although non-negligible, is absolutely unsatisfactory;
the percentage of patients showing total remission, without metastases originated
recurrence, is too low to qualify this particular therapy as a basis for a cure.
[0005] The reason for such a low efficacy cannot be attributed to an unpredictable mechanism,
upon which the treatment is based, since heat induced cell necrosis is a well known
fact, no longer debatable. The reason why hyperthermia, as cancer therapy, is only
occasionally successful originates from the fact that it relies on too small a difference
in irreversible-damage threshold-temperature between normal and neoplastic cells.
[0006] Such restriction is a necessary precaution for the safety of the patient, since no
method nor machine exists, as at today, to deliver the required heat only to the malignant
presence in the body.
[0007] The use of elevated temperature for the treatment of cancer goes back to ancient
times as total-body hyperthermia, while localized hyperthermia is a product of relatively
recent times, utilizing Radio Frequency or Microwave technology and even laser energy
sources.
[0008] But again all of the above rely on the indiscriminate exposure of tissue to elevated
temperature and are therefore restricted in scope because they must rely exclusively
on the questionable and variable higher sensitivity to temperature displayed by malignant
tumors.
[0009] More recently fractionated doses of Radiofrequency Hyperthermia have been proven
effective, still relying on the assumed greater heat sensitivity of neoplastic growth;
the procedures and results are described in Journal of Dermatol. Surg. Oncology, Vol.
15 pages 845 to 849 (1989), in an article entitled "Radiofrequency Hyperthermia Therapy
of Murine Melanoma: A Comparison of Fractionated Versus Single-Dose Treatments".
[0010] However even if encouraging, still the method is clumsy and it is not backed by the
existence of a commercially viable hardware system.
[0011] Although still experimental, one commercially available technique called Photodynamic
Therapy appears to resemble very closely the hereby introduced method (i.e. QUETBISM),
but at the same time is totally off this target and it is also missing a truly effective
hardware system.
[0012] However Photodynamic Therapy, like QUETBISM, is also taking advantage of the already
mentioned fact that cancerous cell tend to retain chemicals and chromophores much
longer than healthy tissues. On the other hand Photodynamic Therapy is relying on
an alleged chemical reaction which supposedly occurs when HPD retaining tissue is
exposed to light of a specific wavelength, as described in many published Research
papers one of which is: "Pharmacological Modulation of Photodynamic Therapy with Hematoporphyrin
Derivative and Light" appearing in "Cancer Research", Vol 47, pages 971-974 (1987).
As an alternative cancer treatment this therapy method is offered to the public by
QLT of Vancouver, BC.
[0013] Finally, the ability to selectively affect stained tissue, under illumination by
laser light of adequate wavelength, is empirically confirmed with a research report,
herein enclosed by reference, published in the Proceedings of the National Academy
of Science, USA, Vol. 85, pages 5454-5458 (Aug 1988) and entitled: "Selective Destruction
of Protein Function by Chromophore-Assisted Laser Inactivation".
[0014] There are several objectives to the present invention and they may be summarized
as follows:
First objective is to provide a self sufficient non-synergetic technique for the effective
obliteration of unwanted extraneous presence in the human or animal tissues, tumor
growth or viral contaminants that they might be; such therapy is in fact called Enhanced
Hyperthermia. With "tissues" is here meant any aggregation of cells besides body tissues,
i.e. also blood.
[0015] Second objective is to provide the apparatus necessary to implement such method;
namely: the opto-electronic hardware (LAILT System).
[0016] Third objective is to provide the subsystem capable to deliver the required energy
to any location of interest within the body, for the treatment of malignant growths.
[0017] Fourth objective is to provide the modification to the main hardware system required
to transform it from a Cancer Treatment Device to a Blood Viral Contaminants Treatment
Device; namely: the variations between the LAILT System I and II.
[0018] The final objective is to establish guidelines on the type and characteristics of
the family of non-toxic compounds which may be used to correctly implement the Enhanced
Hyperthermia Treatment.
[0019] The above stated objectives were achieved by the present invention, that provides
a method of selectively removing cellular or viral contaminants from human or animal
tissues according to claim 1.
[0020] The invention also provides an apparatus for performing above method, according to
claim 6.
[0021] Moreover, the invention relates to a method of cosmetic treatment of human or animal
skin according to claim 17.
[0022] The invention being discussed has taken all the positive aspect of recent research
efforts and presently used techniques and has given life to the method according to
present invention, i.e. Enhanced Hyperthermia, which combines the guiding principles
of most of the existing methods with the simple Quantum Physics' principle of Blackbody
radiation.
[0023] Selective targeting of only malignant tissue is achieved through the widely utilized
standard method of neoplastic tissue tagging, followed by illumination with Quantum
Energy, namely laser light of a wavelength not readily absorbed by live tissue, under
normal circumstances.
[0024] Requirement on the tagging agent are: non-toxicity to human cells and a spectrum
of absorption with a maximum in the frequency range of the light source utilized.
[0025] Final and main feature, that gives the invention a practical general use, is the
invention apparatus, i.e. the LAILT System, which can deliver laser light to any desired
physical location and selectively produce irreversible damage to cell protein, without
causing charring or secondary damage, on account of design features which render the
power output controllable and uniformly distributed.
[0026] The invention will now be disclosed in further detail with reference to accompanying
and non limiting drawings, where:
- FIG.1 is an elementary visualization of the mechanism of light absorption by tissues
with different pigmentation.
- FIG. 2 is a diagram visualization of an embodiment of the invention, with a symbolic
number of array sources for monochromatic light.
- FIG. 3 is a schematic representation of a preferred embodiment of an individual channel's
driver circuit.
- FIG. 4-7 are a schematic representation of a preferred peripheral attachment for proper
delivery.
- FIG. 8 is a diagram of a modified internal layout, required for a different application
of the invention.
[0027] From the medical point of view, the invention takes into account what has been done
to this point in the treatment of cancer, combines several partially successful approved
techniques and brings the entire ensemble a step forward, above and beyond what each
and every method was intended or has been interpreted to be doing, and so arrives
at a successful solution which has a full theoretical explanation.
[0028] From the technology point of view, the invention is taking semi off-the-shelf opto-electronic
components and is utilizing them in a manner different enough from standard procedures
to create new and inventive method (QUETBISM) and apparatus.
[0029] As already pointed out QUETBISM represents the method for delivery of an improved
form of hyperthermia, identified by the inventors with the name of "Enhanced Hyperthermia".
[0030] Based on sound and already proven principles of physics and biology, QUETBISM produces
Enhanced Hyperthermia within a specific target, through the utilization of one of
the LAILT Systems.
[0031] The actual bio-mechanism requires the intra venous injection of a chomophore carrying
compound, which is non-toxic and does not causes any particular chemical reaction
within the tissue, but simply delivers the stain to the general location.
[0032] Based on an important finding already widely exployted in many other cancer treatments,
after a waiting period of 36 to 48 hours, healthy cell will have eliminated the compound
from their structure, while the sick cells will not have. Therefore they will maintain
a different index of absorption, at least for light of the selected wave length.
[0033] The LAILT apparatus will then be used to illuminate the general area and, since its
wavelength was specifically selected to be in a range of negligible absorption by
normal tissue, only the abnormal cells 3, retaining the stain, will reach the target
temperature of 50 degrees Celsius.
[0034] At such temperature cell necrosis is certain; however the surrounding healthy cells
3a, now free of stain, will not be able to reach a temperature greater that 42-43
degrees Celsius, which is still within a safe margin for survival, especially for
normal cells (fig. 1).
[0035] For these reasons, this innovative treatment will not require the assistance of imaging
devices, nor it will require the incorporation of temperature monitoring instruments.
[0036] The LAILT apparatus is designed to safely deliver, to the general surroundings of
a targeted area, a controlled amount of energy low enough to cause only minor discomfort
and totally reversible damage, if any, to healthy tissue but sufficient to produce
irreversible damage to regions displaying abnormal index of absorption, artificially
induced with the tagging process.
[0037] This goal cannot be achieved with the assistance of any traditional laser system,
presently used in medicine.
[0038] The LAILT System I is so compact that it may be contained in a metal casing with
the approximate size of 47x31x18 cm and may be carried in a compact suitcase or a
slightly oversized attache; it is designed (fig. 2) to plug directly on an ordinary
120 (or 220) Volt standard wall outlet and does not require an actual cooling system.
The electrical cord 22 coming from the wall outlet 23 feeds both a series of independent
power supplies 24 and a DC transformer 25. The transformer feeds two mini fans 26,
which represent the only cooling apparatus needed. Each power supply feeds the driver
circuits of three channels 27; where the word channels is here used to identify the
laser energy sources.
[0039] Consequently the actual number of power supplies depends solely on the number of
channels used in the system, which in turn depends on the specific application.
[0040] The energy sources in question are in fact semiconductor lasers of high output and
uniform, unfocused far field pattern, with an output rating of at least 200 mW at
the window or fiber tip, depending on the application.
[0041] For the LAILT System I, the semiconductor lasers utilized, also called laser diodes
because of their design layout, have a fiberoptic line 15 approximately one (1) meter
long or thereabout attached at the emission window; the rated output at the laser
light emission sources 28, i.e. the tips of the fibers, is in the general range of
150-300 mW.
[0042] However for the specific need of the Enhanced Hyperthermia treatment, the devices
are not driven to their maximum rating since, for curative purposes, it is not necessary
to induce tissue charring.
[0043] Each laser is independently powered by a separate driver circuit 1, (fig. 3), to
take into account and be protected from individual minor variation in rating; so that
each channel can deliver on tissue an equal amount of power and the combined output
beam can furnish to the illumination area a uniform amount of energy.
[0044] Each driver circuit is also provided with safety oriented filtering features, to
eliminate the costly possibility of damage to the very sensitive semiconductor lasers.
[0045] Said circuits are also equipped with an input power control device (not shown), manually
operated and accessible from a numbered nub on the external top portion of the casing,
below each numbered meter, in turn intended to provide visual confirmation of the
exact amount of input provided to each and every energy source.
[0046] The identical driver circuits 1 are at this point very simple, efficient and to the
point. At a later date, they will eventually be improved to render the LAILT System
more user friendly; but the basic structure will remain unchanged because it is capable
to guarantee safe and controlled operation of the system. More specifically, the basic
circuitry comprises : control means 4,5 to control the voltage drop from power source
to semiconductor laser; protecting means 6,7 to protect said semiconductor laser 8
from current surges and voltage spikes; filtering means to protect the semiconductor
laser from ground surges and spikes; and control means 10-13 to control biasing of
semiconductor laser.
[0047] As it is clearly comprehensible from the schematic in FIG. 3, the input power from
2 is controlled with variable resistor 5 followed by diode 4, whose presence only
serves to ensure finely adjusted voltage drop.
[0048] At point A the line separates into three parallel resistor networks, in this way
effectively dividing the total current into branches of appropriate level. This is
done to provide the semiconductor laser 8 with correct biasing and a variable drive
current, which in turn permits operation of said laser throughout its full range of
output capability.
[0049] The branch including connection point C is the one containing the semiconductor laser
and, for reasons already indicated, it is designed to see a current flow variable
from the lasing threshold of approximately 175 mAmps to the maximum allowable of approximately
800 mAmps.
[0050] The branch containing connection point B includes one fixed resistor 11 and a variable
one 12, in addition to one Amp meter 14.
[0051] The presence of this parallel branch serves the double purpose of providing an adjustable
current shunt for the semiconductor laser as well as an indirect monitor of the diode's
drive current.
[0052] Fixed resistor 11 establishes the minimum conductance (G) of this branch, while variable
resistor 12 allows for adjustments. An increase in the value of 12 causes an increase
in the laser's drive current, while a decrease in the value of the same resistor produces
a reduction in laser light output power.
[0053] The meter 14 following 12 allows the trained user to monitor the channel, by determining
the semiconductor laser's drive current through a simple subtraction of the value
indicated by the meter from the known total current.
[0054] In the branch containing the laser, coil 7 is incorporated to delay any eventual
surge current, until the Zener Diode 6 has the opportunity to turn on and divert from
the very sensitive light source 8 any voltage spike.
[0055] Additionally diode 9 is located on the cathode side of the semiconductor laser to
filter out ground surges and spikes.
[0056] Variable resistor 13 is incorporated to allow for finer tuning of current adjustments
in both B and C branches.
[0057] The three parallel branches rejoin at point E, proceed to include point F in their
path and finally flow through fixed resistor 10, which in conjuntion with the total
resistence of of the three branch circuit helps establish proper loading of the power
supply.
[0058] To allow proper monitoring of each branch from the external side of the casing and
only as an additional precaution, two LED are added to circuit with relative biasing
resistors to merely confirm that current is actually flowing through the whole circuit
and the branch containing the laser. No illuminating signal is necessary in the third
branch, since the meter itself is the utilized indicator.
[0059] Finally and not shown in any of the drawings, for the LAILT System I only the Quantum
Energy emerges from the tip of a fiberoptic line installed as part of the Semiconductor
laser at the original manufacturer's site.
[0060] The central feature, without which the proper delivery of Enhanced Hyperthermia would
not be possible, and, at the same time one of several technological innovations in
the LAILT System, is the presence of multiple fiberoptic guided beams of nearly identical
power, originating from distinct individually driven laser energy sources, which ensure
uniform distribution of power within the illuminated region.
[0061] The latter characteristic is vital for the certain acquisition of the target temperature
(50 degrees Celsius) by tagged tissue only, as the only way to ensure its total necrosis.
[0062] Systems equipped with multiple fiberoptic lines, utilizing the electromagnetic energy
originating from one single powerful laser source, cannot allow for proper control
of the output power.
[0063] In other words, the present invention apparatus provides also a method for the generation
of uniform and unfocused monochromatic laser light and irradiation by the same of
an extended area.
[0064] The other key factor is the utilization of semiconductor laser technology, which
not only provide monochromatic radiation, in the exact range not significantly absorbed
by human tissue under normal circumstances, but it also renders possible the design
of an "Array of Arrays", namely the LAILT System, which, even as a system of multiple
laser sources, displays very limited input power consumption, and it is easily transportable,
practical, does not require a clumsy cooling apparatus and is still of reasonable
cost, contrary to what a system of multiple traditional lasers would be.
[0065] In the preferred embodiment the two fans 26 are strategically positioned, with respect
to driver circuits, to provide spread and uniform ventilation of the array of said
circuits 27. Each laser source is firmly resting on the already mentioned angled heat
sinks, and as a whole are positioned in apparent disorderly fashion; in reality the
distribution has been so designed to ensure that there is a reasonably close distance
covered and a minimum overlapping in the fiber path, as they come together in a bundle
and are so directed toward the exit opening positioned to the side of the casing.
This distribution is the most adequate and consistent with the need to limit the spacial
demands. Finally, at the exit point in the casing, the fiber bundle is firmly braced
to the internal side of the apparatus external packaging, for the sole purpose of
limiting the stress, deriving from motion in repeated usage, on the fiber optic attachement
located for each laser source at the window of emission.
[0066] In the LAILT apparatus to be used for the treatment of melanoma the delivery attachment
will be as represented in FIG. 4 to 7, where a plexiglass tube 17 is used to guide,
separate and maintain securely in place the various fiber lines 15.
[0067] This goal is achieved with a multi sections (three to five or possibly more) solid
acrylic tube 17, where channels 18 have been etched for the passage of the fibers
15 in a smoothly progressive diverging fashion at first, until appropriate separation
has been achieved and subsequently in a collimated pattern until the exit opening
19 is reached; at said opening the tip 16 of the optical fiber protrudes from the
channel and is kept away from direct contact with the tube by means of an enlarged
cone shaped channel end 19, and from the surface of the skin by a simple base collar
cladding 20 doubling also as stand thanks to a cone shaped end portion 21. All the
above features in the design of the delivery attachment are necessary precautions
not only for the convenient handling of the tool, but especially to ensure that the
tips of the various fiber lines do not come in direct contact with each other or the
surface of the skin and do not in this way cause self damage nor generate unnecessary
overheating of the target.
[0068] The total length of the delivery tubule is approximately 13 cm and the various sections
snap into place through the use of incorporated pins 17a.
[0069] Finally the tagging agent necessary to alter the index of absorption of the neoplastic
tissue is not a uniquely identified nor an exclusive product, since no specific or
obscure chemical reaction are at the basis of the process.
[0070] Again all is required of any adequate product is to be capable to carry an energy
transferring compound, that is preferably a chemically inert and pharmaceutically
acceptable chromophore, to the desired site, which does not need precise spacial identification,
but merely an approximate one simply pointing to the general region.
[0071] Restrictions on the chromophore are: non toxicity to the human body and most preferably
a shade of eighter green or black coloration. In the studies reported in the previously
mentioned article discussing chromophore-assisted laser inactivation and during that
particular research effort, Malachite Green was used as stain in question, but, although
within the acceptable chromatic range, malachite green is not proven to be totally
non-toxic to the body.
[0072] In vivo and in vitro tests were carried out according to the following examples.
Example 1
[0073] In vivo tests were effected according to the following procedure :
Subject, caucasian adult male, displaying a tattoo on the right forearm, agreed to
serve as volunteer in a verification test. In this case, the contaminants, i.e. colored
cells forming the tattoo pattern, were already stained by the tattoo ink : Therefore,
no staining step was required.
[0074] Without receiving general or local anesthetic of any type or form, he exposed the
general area of interest in the forearm to illumination from the fiber tip bundle
located at about 1.5 cm distance from the skin surface. Since the general area of
interest was much larger than the illumination spot originating from the apparatus,
the exposed portion was methodically shifted after a time interval averaging approximately
20 seconds. Since illuminated spot temperature monitoring was not possible under such
test conditions, simply from the observed effect on the stained skin portion only,
it was possible to conclude that the temperature reached must have been in the range
of 60 °C.
[0075] More significantly, the results of the in-vivo testing were that the cells carring
green ink were irreversibly damaged, actually displaying excessive burning, while
the surrounding unstained cells concomitantly exposed to the same illumination pattern,
did not suffer any reportable disconfort nor displayed at any time any form of damage.
[0076] This was done to demonstrate that any product of the adequate color will produce
the wanted result and that its selection would be mere a matter of preference or practicality.
Possible application of the invention to cosmetic treatment of skin is apparent from
this test.
Example 2
[0077] In vitro tests were effected according to the following procedure.
[0078] About 0.5 cc of Agar gel were stained with a 5%concentration of McCornic Food Coloring
containing FD&C Yellow # 5 and FD&C Blue #1. The stained Agar gel was exposed to illumination
from the invention apparatus, utilized with an output of 200 milliWatts, from a 1.5
cm distance for 90 seconds time interval and longer. A thermocouple tip immersed in
the gel was used for immediate and correct temperature read-out.
[0079] An equal volume of unstained Agar gel was also subjected to identical condition of
exposure.
[0080] The results showed that stained Agar gel did reach a 50 °C temperature within the
initial 90 seconds, while non stained agar gel did not go above the 43 °C mark, even
well beyond the 90 sec. time limit.
[0081] In the actual treatment of patients it will preferably be used a more convenient
compound, like one of the stain already used for the visualization of cancer; one
of which is the one identified by the name of "Fresh Green".
[0082] Similarly, it will also be preferred the use of some of the products which display
affinity to highly acid tissue as cancer and are used to quickly identify the neoplastic
site, without the need of a waiting period.
[0083] According to another preferred embodiment of the invention, these products will be
admixed with a color in the proper range, to actually shorten the waiting period prior
to illumination treatment.
[0084] The same principle and technique may be applied in the elimination of viral contaminant
in the blood, although a very different delivery apparatus will be needed in such
a case.
[0085] Again, in this different application, the main structure of the LAILT System remains
unaltered and so do the various driver circuits; only the internal arrangement of
the "Array of Arrays" is modified, as shown in the black box diagram of FIG. 8. The
differences from the previously disclosed embodiment are that laser sources A to L
do not need to be oriented in a distance balancing fashion, since slightly different
semiconductor lasers are utilized in this design and therefore it is only necessary
to provide uniform illumination of the target. The difference in these laser sources
only applies to the external packaging and it refers to the fact that they do not
carry a fiberoptic attachment and relative fiber, but they simply possess an emission
window from where the beam irradiate with a far field pattern of slightly oval cross-section
instead of the circular one of the output from the fiberoptics. However, in this case
the exiting beam retains the coherency characteristic of lasers, which is lost in
the case of devices provided with fiberoptic lines. Finally, the sources will be resting
on ordinary heat sinks with emission windows facing upward, immediately below a clear
window area in the apparatus casing.
1. A method of selectively removing cellular or viral contaminants from tissues of human
or animal patients in the need thereof, by hyperthermia therapy, characterized in
comprising the steps of :
selectively staining, if necessary, said contaminants by means of an energy transferring
compound; and
irradiating the tissue area containing said contaminants with uniform, unfocused laser
light of a wavelength that gives rise to absorption by said energy transferring compound
but is not substantially absorbed by surrounding non-stained tissue, said irradiation
being carried out for a time sufficient to have said energy transferring compounds
release energy to stained contaminants to heat them at least to a temperature resulting
in their irreversible damage.
2. A method according to claim 1, wherein said energy transferring compound is a chemically
inert chromophore and selective staining is obtained by selective retention of said
chromophore by contaminants.
3. A method according to claim 2, wherein contaminants are cancer cells.
4. A method according to claim 3, wherein said chromophore is administered by intra-venous
injection.
5. A method according to any previous claim, wherein said laser light has an output within
the range from 100 to 300 milliWatts.
6. An apparatus for selectively removing cellular or viral contaminants from human or
animal tissues by hyperthermia therapy, characterized in that it comprises a plurality
of distinct laser light generating means for generating laser light having wavelength
that is not significantly absorbed by health tissues and a plurality of light delivery
means for uniformly irradiating an area of said tissues with said laser light.
7. An apparatus according to claim 6, wherein said laser light generating means is a
semiconductor laser.
8. An apparatus according to claim 7, wherein each semiconductor laser is connected to
a separate driver circuit.
9. An apparatus according to claim 8, wherein said driver circuit comprises : control
means (4,5) to control the voltage drop from power source to semiconductor laser;
protecting means (6,7) to protect said semiconductor laser (8) from current surges
and voltage spikes; filtering means to protect the semiconductor laser from ground
surges and spikes; and control means (10-13) to control biasing of semiconductor laser.
10. An apparatus according to claim 9, wherein said control means for controlling voltage
drop comprises a variable resistor (5) and optionally a diode (4), said protecting
means comprises an impedance coil (7) and a zener diode (6), said filtering means
comprises a diode (9), and said biasing control means comprises one or more fixed
resistors (10,11) and one or more variable resistors. (12,13).
11. An apparatus according to claims 9 or 10, further comprising an ammeter (14) or similar
drive current monitoring means.
12. An apparatus according to any claim 6 to 11, wherein said delivery means comprises
a plurality of optical fibers (15) connected to the light output of each semiconductor
laser (8).
13. An apparatus according to claim 12, further comprising housing means to individually
house and separate from each other the tips (16) of said optical fibers and their
end portions.
14. An apparatus according to claim 13, wherein said housing means comprises a tube (17)
having a plurality of channels (18) each housing one optical fiber (15), each channel
having a cone-shaped end portion (19) housing said fiber tip (16) without contacting
it and in spaced relationship with respect to the patient skin.
15. An apparatus according to claim 14 wherein said tube (17) is provided with a cladding
(20) having cone-shaped end portion (21).
16. An apparatus according to claims 14 or 15, wherein said tube (17) comprises a plurality
of sections.
17. A method for the cosmetic treatment of human or animal skin by removal of irregularly
or undesirably pigmented areas, characterized in that it comprises the steps of :
detecting the maximum wavelength absorption of laser light by said skin areas; optionally
staining said areas with a chromophore or similar energy transferring compound; and
irradiating a skin portion containing the said skin area with uniform, unfocused laser
light of a wavelength that gives rise to absorption by said skin areas or by said
energy transferring compound but is not significantly absorbed by surrounding correctly
pigmented skin.
18. Pharmaceutically acceptable tagging compounds for cancer cells visualization for use
as energy transfer compounds for irradiation with laser light.
19. The use of tagging compounds according to claim 18, in combination with pharmaceutically
acceptable chromophores.